There’s a common critique in science fiction series like Star Trek about the extraterrestrial species not looking ‘alien’ enough, as well as about their technology being strangely similar to our own, not to mention compatible to the point where their widgets can be integrated into terrestrial systems by any plucky engineer. Is this critique justified, or perhaps more succinctly put: if we came across real extraterrestrial life with real extraterrestrial technology, would we even notice? Would an alien widget borrowed of an alien spacecraft even work with our own terrestrial spacecraft’s system?

Within the domain of exobiology there are still plenty of discussions on the possible formation and evolutionary paths conceivable within the Universe, but the overarching consensus seems to be that it’s hard to escape the herding effect of fundamental physics. For lifeforms, carbon-based chemistry is the only reasonable option, and when it comes to technology, it’s hard to not end up at technology using the same physical principles which we presume to exist across the Universe, which would practically guarantee some level of interoperability.

What’s notable here is that over the past years, a number of people have claimed to have observed potential alien technology in our Solar System, in particular the ʻOumuamua asteroid in 2017 and a more recent claim by astrophysicist Abraham Loeb regarding an interstellar meteor that impacted Earth in 2019, which he says could be proof of ‘alien technology’. This raises the question of whether we are literally being pummeled by extraterrestrial spacecraft these days.

Space Is Boring

Most of space is literally just that: seemingly endless stretches with nothing but some electromagnetic radiation and potentially virtual particle pairs briefly zipping about in a vacuum. From the center of the Sun to Neptune’s orbit is 30.11 AU, or approximately 4.5 billion km, and outside the cozy confines of our Solar System it’s a trip of more than 4.2 light years to the next planetary system in the form of Proxima Centauri.

Traveling beyond the bounds of the Milky Way galaxy, distances to other galaxies are measured in millions of light years, meaning that even when traveling at 1 c, traveling to these galaxies would take longer than humans have existed in any form. This means effectively that all the space probes like Voyager 1 and Voyager 2 – which we sent into interstellar space at a relatively leisurely pace of over 30 km/s – will not approach another planetary system until many thousands of years into the future.

Simulated view of the Voyager probes relative to the solar system and heliopause on August 2, 2018. (Credit: NASA)

What this sobering realization also shows us is just how unlikely it is that an extraterrestrial spacecraft would somehow end up in our neighborhood, all the way here in a sparsely populated region of the Milky Way. Perhaps ironically, the likelihood of this happening would be much higher if it was deliberate, rather than a derelict alien space probe. Yet even then in the absence of faster-than-light traveling capacity, such a spacecraft would likely have been underway long before humanity had begun to differentiate itself from the other ape species on Earth, or mammals had begun to throw off the shackles of dinosaur tyranny.

Ultimately, planetary systems even within the same galaxy are rather isolated. This makes the possibility of having even something as mundane as another civilization’s space trash zip through our neighborhood both exceedingly unlikely and extremely exciting. But exactly how do we tell the difference between a comet rich in metals and a sophisticated extraterrestrial probe?

Is It A Rock? Is It A UFO?
Hyperbolic trajectory of ʻOumuamua through the inner Solar System, with the Sun at the focus, showing its position every 7 days. The planet positions are fixed at the perihelion on September 9, 2017. Shown from a three-quarter perspective, roughly aligned to the plane of ʻOumuamua’s path. (Credit: Tomruen, Wikipedia)

When a large enough object enters our solar system, we are likely to pick it up using telescopes, after which we can begin to figure out what exactly it is that we’re dealing with. The easiest clue as to whether we’re dealing with anything interesting is the trajectory and speed of the object, which is why ʻOumuamua was considered to be so interesting, as based on its calculated trajectory it came from far beyond the solar system, making it a rare visitor from probably another solar system within the Milky Way, or even far beyond.

From what we can determine, this particular object has likely been moving through the Milky Way for at least hundreds of thousands and likely billions of Earth years, yet its somewhat unusual elongated shape invited speculation about it being more than just a rocky asteroid, with Abraham Loeb pitching the idea that it was in fact a spaceship. Part of this speculation came from oddities in the asteroid’s velocity as it neared our solar system, but subsequent observations showed the object to be consistent with other, non-extrastellar asteroids. Attempts to detect any radio frequency emissions also led to nothing, and with the asteroid being too far removed from Earth to get a close-up look, much of what we know about it is based on its spectra.

A few years after ʻOumuamua passed silently through our solar system, another interstellar visitor made its presence known in the form of 2I/Borisov, or Borisov for short. This was a comet that made an even briefer visit, finding its path deflected by the Sun before it continued on its trajectory through the Milky Way. Making interstellar visitors even less rare is CNEOS 2014-01-08, which is the meteor that Abraham Loeb got excited about since it’s an interstellar object which not just passed through the solar system, but which actually crashed onto Earth.

After obtaining the 10 km radius of the meteor’s suspected crash site off the coast of Papua New Guinea, Loeb and colleagues recovered some metallic spherules in the area, which he claims to have a composition that points towards the meteor having been an extraterrestrial spacecraft of some type with astounding alien properties. Whether these spherules are in fact connected to the meteor is still left up for interpretation, as they are not composed out of any alien metals, just the same iron, silicon, magnesium and titanium you’d expect to find on and outside Earth.

Axiom Vs Infinity

Perhaps what drives some of us to believe in ‘alien technology’ to be somehow magical is the belief that there must be something beyond the boring physics which we are currently trapped in. When we consider for example that many people put their faith in supernatural beings, fantastic existences beyond anything we can observe or measure, the ability of crystals, magnets and even plain water to effect reality in ways beyond any reasonable explanation, not to mention harmful effects of things long after no negative effect has been demonstrated.

To the rational, scientific mind, the Universe we have found ourselves in can be a source of marvel, but it’s nevertheless a purely rational and deterministic system. Through the scientific method we are able to convert observations into theorems and theories which we can then subject to validation through experimental and observational data. If the data fits the theory’s prediction, it passes, if it does not, either the theory is wrong, or the way the data was obtained was flawed.

Where some may question whether we really know anything is when they learn about the concept of axioms, which are essentially assumptions, and the axiomatic systems that underlies much of today’s mathematics and ultimately also some elements of physics. Yet as flawed as it may seem that we would hold certain truths to be self-evident, they’re a practical way to prevent issues like infinite regression as we try to define a set of terms. If not, one could conceivably discard the axiom that ‘1 equals 1’ by dismantling the axiomatic definitions underlying the property of one term equaling another.

Self-evidence here is not a sign of laziness, but rather one of fundamental understanding. This is exemplified by the fundamental electrical components which were postulated and gradually proven to exist based on an increasing understanding of electrical circuits and their potential properties. Of these the components, the resistor, capacitor and inductor were first discovered, followed eventually by the memristor.

What this demonstrates is how improved understanding of one part of a system can allow us to predict that which we have yet to discover, even if it’s something that defies intuitive understanding like magnetic monopoles.

Alien Is Relative

As someone once put it: “Where are all the time travelers?” in reference to the concept of time travel being possible, which is a statement that should put to rest the idea of either time travel being invented, or humanity going extinct before it is able to do so. Part of existing in this universe is to accept that there’s so much that we do not know, and perhaps will never know. All we know today is that even within the minuscule time period of a hundred rotations of the Earth around the Sun, humankind has fought a number of world wars, discovered modern medicine, invented computer technology and semiconductors.

To our ancestors and even to those who are living well into their twilight years today, the world we inhabit today seems alien in many ways. What will human technology look like in a hundred years, or a thousand? What about 100,000 years from now? Within the timescale of the Universe, those are still tiny numbers during which a particularly shaped space rock can leisurely zip around the Milky Way a few times, each time passing by a specific solar system in which over billions of years some goop turned into multicellular organisms which eventually turned into mammals that invented sliced bread and computers.

Is there truly extraterrestrial life out there, or is it mostly what we keep telling ourselves to feel less lonely in this grand and yet so empty Universe? Whatever may be the case, if we ever do meet up, we’re likely to be able to exchange technology, even if it’s the equivalent of wiring up a 1930s vacuum tube radio to a 2020s super computer. Which will naturally be just where we have that plucky engineer jump in.